We have recently found that urine from patients with transitional cell carcinoma of the bladder and renal cell carcinoma stimulate significantly greater migration of capillary and endothelial Balb 3T3 cells than urine from either normal individuals, patients with benign diseases or patients who have had their tumors removed. Our aim is to further investigate this phenomenon and determine if this property in urine can be used to detect new and recurrent bladder and kidney tumors. We plan to determine what factors upset the level of cell migration and what can be done to standardize the assay. We will also compare this assay with urinary cytology to determine the potential usefulness as a screening test in high risk patients. We plan to further characterize and begin to purify the substance in urine responsible for this observation, because the long term objective of this work is to develop a new, noninvasive test for bladder and kidney tumors that can be used on a widespread basis. Such a test would result in better management of patients with these diseases.